Which statement best differentiates atypical antipsychotics from conventional ones?

• A. Atypical antipsychotics cause more EPS than typical antipsychotics.
• B. Atypical antipsychotics do not cause weight gain.
• C. Atypical antipsychotics have fewer metabolic effects than typical antipsychotics.
• D. Atypical antipsychotics have lower risk of extrapyramidal symptoms but higher risk of weight gain and metabolic effects.

Answer: (D)

A key distinction between atypical and conventional antipsychotics is their side‑effect profile. Atypical (second‑generation) antipsychotics tend to cause fewer extrapyramidal symptoms because they not only block dopamine D2 receptors but also strongly antagonize 5-HT2A receptors, which helps reduce motor pathway disruptions that lead to EPS. However, they carry a higher risk of metabolic issues, including weight gain, insulin resistance, and dyslipidemia. This combination—lower EPS but higher metabolic risk—best differentiates atypical from conventional antipsychotics. Conventional antipsychotics, by contrast, have a higher likelihood of EPS due to potent dopamine blockade in motor pathways and generally do not carry the same pattern of metabolic effects seen with many atypicals.